Ergonomics Awareness Training by kig45481

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									Navy Ergonomics Program

             Awareness Training
                                 Technical Support Services
                           by Naval Facilities Engineering Command

 Cathy Rothwell, PE Ergonomic Program Manager

 Mindy Smith, MEng, AEP Ergonomic Technical Support - East Coast

 Theresa Stack, MS, AEP Ergonomic Technical Support- West Coast
 What is Ergonomics?          er·go·nom·ics \, ûrg-go-'näm-iks

‘Ergonomics’ is derived from two Greek words
  Ergon meaning work
  Nomos meaning principles or laws

      Ergonomics = The Science of Work
Ergonomics is not a new science, although the term
  has become more common lately. The phrase
  was first coined in 1857.
 What is Ergonomics?             er·go·nom·ics \, ûrg-go-'näm-iks

Common Definitions
  “Ergonomics is essentially fitting the workplace
    to the worker. The better the fit the higher the
    level of safety and worker efficiency.” Fitting the
    Task to the Human ~ Grandjean 1990

  “Ergonomics removes barriers to quality,
    productivity and human performance by fitting
    products, tasks, and environments to people.”
      What are the consequences
        of poor Ergonomics?
Why are we hearing about ergonomics now?
 Are there new hazards at work? No!

  Consequences of poor workplace design were first
   documented in the 17th century.

Have you ever heard of these?

  Historic Occupational Disorders - house-maid’s
   knee, washer woman’s thumb, writer’s cramp, data-
   processing disease, clergyman’s knee, nun’s
   bursitis, weaver’s bottom, dustman’s shoulder,
   tailor’s ankle
     Do these historic occupational
       disorders still exist? Yes!
They are part of a broad category of injuries and
 disorders called Musculoskeletal Disorders
 (MSDs). MSDs are not usually caused by acute trauma,
  but occur slowly over time due to repetitive injuries to the
  soft tissues (muscles, tendons, ligaments, joints, cartilage)
  and nervous system

MSDs can happen to anyone from office workers
 and industrial employees to athletes and hobbyists

                                                 Before   Improved
     Do these historic occupational
       disorders still exist? Yes!
Work-Related Musculoskeletal Disorders
 (WMSDs) are MSDs that are caused or made worse by
  work methods and environment. They occur when the
  physical capabilities of the worker do not match the
  physical requirements of the job

Common MSDs:                             Before   Improved

  Tendonitis, Epicondylitis (Tennis or Golfer’s Elbow),
   Bursitis, Trigger Finger, Carpal Tunnel Syndrome,
   Back Strain
     What are aliases for WMSDs?

Work-related MSDs go by many other names:

  Repetitive Strain or Stress Injury (RSI)
  Repetitive Motion Injury (RMI)
  Cumulative Trauma Disorder (CTD)
  Overuse Syndrome
  Activity-related Pain Syndrome

Ergonomics can help prevent MSDs that are
caused or aggravated by working conditions
  What characteristics of your job put
        you at risk for MSDs?

Prolonged, repeated or extreme exposure to multiple
WMSD risk factors can cause damage to a worker’s
body. Risk Factors include:

Repetition                 Excessive Force
Awkward Postures           Vibration
Static Postures            Compression
Cold Temperatures          Inadequate Recovery

  Repetition = Performing the same motion
          or group of motions excessively.

Examples of Repetition
  Repeating the same motion every
   few seconds or repeating a cycle of
   motions involving the same body
   parts more than twice per minute for
   more than 2 consecutive hours in a
   row                                     Excessive
                                           repetition of
  Using a tool or an input device, such   movements can
   as a keyboard in a steady manner for    irritate tendons
   more than 4 hours total in a work day   and increase
                                           pressure on
 Awkward Postures = Postures outside
                    of neutral.

Neutral is the optimal
 position of each
 joint that provides
 the most strength
 and control

                         Before: Lab technician tilts   Ergonomic Improvement:
Awkward or unsupported   his neck forward to view       Sailor easily views the
                         the screen into a non-         screen from a neutral
postures that stretch    neutral posture. He also       posture. The workstation
physical limits, can     bends over resting on his
                         forearms to write on the
                                                        adjusts to accommodate
                                                        different working heights
compress nerves and      documents.                     and users. When standing,
                                                        work should be about elbow
irritate tendons                                        height.
Awkward Postures = Postures outside
                     of neutral.

Examples of Awkward Postures:
Repeatedly raising or working
 with the hand(s) above the
 head or the elbow(s) above
 the shoulder(s) for more than
 2 hours per day
Kneeling or squatting for more
 than 2 hours total per day
Working with the back, neck
 or wrist bent or twisted for
 more then 2 hours per day
Sitting with feet unsupported
    Neutral Posture for Computer Use
Position the monitor about an
arm’s length away directly in                     Adjust the seat height
front of you. The top of the                      so upper arms hang
screen no higher than eye                         vertically, elbows bent
level (Unless the user wears                      about 90 degrees,
bi-focal glasses)                                 shoulders relaxed and
                                                  wrists fairly straight
 Use a document
 holder close to the
 monitor rather than                                 Adjust
 laying papers flat                                  the back
                Mouse should be next to              rest to
                keyboard both at a height            provide
                equivalent to the user’s seated      firm
                elbow height                         support
                                                     to the
                                                     small of
Knees comfortably bent with                          the back
feet resting on the floor. If the
chair is raised so the keyboard
height equals elbow height, use
a footrest .
                             Static Postures =
       Holding the same position or using the
   same muscles for extended periods of time

Static postures, or positions that a worker must hold for long
periods of time, can restrict blood flow and damage muscles

Before: Mechanic maintains a static posture   Ergonomic Improvement: Creeper supports mechanic
holding arms and hands elevated while         and brings him closer to the task
repairing aircraft
                 Cold Temperatures

Working in environments
 below 68 degrees can
 cause nerve damage.

 Working in cold
 temperatures can adversely
 affect a worker’s
 coordination and manual
 dexterity and cause a
 worker to use more force
 than is required to perform a
   Force = A strong physical exertion
                             Before: Three
Exertion = the tension       sailors climb
                             on refuse bin
  produced by muscles        to dump
                             laundry cart full
  and transmitted            of waste. They
                             risk back strain
                             and lacerations
  through tendons            while tipping
                             cart over to
                             empty it.

Excessive muscle tension      Ergonomic
can contract muscles to       Improvement:
                              One worker
their maximum capability      easily dumps
                              waste in half
which can lead to fatigue     the time.
and possible damage to the
muscles and other tissues.
   Force = A strong physical exertion

Examples of forceful exertions:
       more then 75 pounds at any one time;
       more then 55 pounds more than 10 times per day;
       more then 25 pounds from a height below the knees, above the
        shoulders, or at arms length more than 25 times per day.
    Pushing / pulling with more than 20 pounds of initial
     force for more than 2 hours per day
    Pinching (pencil type grip) an unsupported object weighing
     2 or more pounds per hand for more than 2 hours per
    Gripping an unsupported object weighing 10 pounds or
     more per hand for more than 2 hours per day
                        Vibration - Single Point

Hand and Arm                                   Examples of vibrating tools
 exposure results from                          Using vibrating tools or
                                                 equipment that typically have
 vibrating objects such                          high vibration levels for more
 as power tools.                                 then 30 minutes a day (chain
                                                 saws, jack hammers,
                                                 percussive tools, riveting or
                                                 chipping hammers).
                                                Using tools or equipment
                                                 that typically have moderate
                                                 vibration levels for more then
Before: Sailor is exposed to vibration above     2 hours total per day (jig
ACGIH TLV guidelines
                                                 saws, grinders or sanders).
Ergonomic Improvement: Lower vibration tool
reduces vibration to safe levels
            Vibration - Whole Body

Whole Body
 exposure to
 vibration results
 from vehicles such
 as forklifts, cranes,
 trucks, buses
 subways and

 High or prolonged exposure to whole body vibration can affect
 the skeletal muscles and cause low- back pain
 Compression = soft tissue is compressed
between the bone and a hard or sharp object

Compression, from grasping or contacting edges like tool
handles, can concentrate force on small areas of the body,
reduce blood flow and nerve transmission and damage tendons
and tendon sheaths

     Before: Worker rests his wrists on the
                                               Ergonomic Improvement: Worker rests her
     sharp tray edges. His wrist is extended
                                               wrists and forearms on a padded surface.
     into a non-neutral posture.
                                               Wrist and forearms are in a neutral position.
 Compression = soft tissue is compressed
between the bone and a hard or sharp object

Compression, from grasping or contacting edges like tool
handles, can concentrate force on small areas of the body,
reduce blood flow and nerve transmission and damage tendons
and tendon sheaths
                                                               Before: Tool
                                                               handles are
                                                               small and
                                                               angular requiring
                                                               the worker to
                                                               grasp tightly
                                                               against sharp

       Ergonomic Improvement: Tool handle is formed to fit the worker’s hand which
       requires less grip strength or force and a more user-friendly tool
Can Other Factors Contribute to MSDs?

                      Not all ergonomic risk factors
                       are physical, some are
                       related to the work

Stress on the job, quotas, peer pressure, boredom,
conflicts with co-workers and supervisors,
deadlines, and even a lack of control over what you
do can contribute to (but not cause) MSDs
    Can Personal Factors Contribute to

Some people are at greater risk of developing
MSDs due to personal factors

Age and Gender                Pregnancy
Hobbies                       Obesity
Previous Injuries             Medications
Physical Condition            Smoking
Medical conditions            Fatigue
 (diabetes and arthritis)
What are MSD Signs and Symptoms?

Painful aching joints, muscles
Pain, tingling or numbness
Fingers or toes turning white
Shooting or stabbing pains
Swelling or inflammation
Stiffness or difficulty moving
Burning sensation
Pain during the night
What should you do if you experience a
      MSD Sign or Symptom?

          If you experience signs or symptoms
             of MSDs, report it to a supervisor,
             industrial hygienist or safety

          If pain or discomfort does not go
             away when you leave work or
             interferes with you carrying out
             normal activities, see an
             occupational health nurse or
       How do you Avoid MSDs?
      Work Smarter, Not Harder!

Work in neutral        Use proper lifting
 postures                techniques and lift aides
Reduce excessive       Ask for assistance with
 force & repetition      difficult tasks
Keep everything in
 easy reach and at      Take micro-breaks
 proper heights          (stand, stretch, change
Keep warm               tasks)
Minimize static        Maintain a comfortable
 unsupported postures    environment
 and pressure points
  What can ergonomics do for you?

The anticipated benefits of good workplace design

  Improved health and safety by reducing work-
   related injuries and disorders

  Improved comfort, morale and job satisfaction

  Improved productivity and reduced workers’
   compensation costs and employee turnover

                                        Before   Improved
    Where to go for more information

 NAVFAC web site – contains ergonomic tools, resources, guides,
  training and awareness material (Select - Program Categories - Ergonomics)

 NAVOSH website- Contains success stories of ergonomic interventions
  throughout the Navy

 DoD Ergonomic Working Group - Contains Guide to Setting up an
  Ergonomics Program and many other tools

 NIOSH- order many free ergonomic documents including Elements of
  Ergonomics Programs and Cumulative Trauma Disorders in the

 Navy Policy 5100.23F Chapter 23 – Ergonomic Program

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